Effect of Insulin Therapy on Vagina in Diabetic Rat / 대한해부학회지

The most commonly reported sexual problems in diabetic women are sexual arousal disorder and a lack of vaginal lubrication. The aims of this study were to investigate the vaginal structural changes and expressions of TGF-beta1, Ec-NOS and estrogen receptor alphaby histochemistry, immunohistochemistry and Western blot analysis in diabetic and insulin-treated diabetic rats. The mean blood glucose levels were significantly increased in the diabetic rats (453+/-88.4 mg/dL)compared to the control group (79+/-6 mg/dL)and insulin-treated diabetic rats (56.7+/-0.6 mg/dL).The vaginal wall in control rat showed 6~11 layered stratified squamous epithelial lining and submucosal smooth muscle, connective tissue and vasculatures. In diabetic rat, the vaginal epithelium was reduced to 2~6 layers and the submucosal vasculatures were decreased n size and number.Collagen fibers were increased and irregularly distorted arrangement. Insulin-treated diabetic rat showed similar morphologic features as control rat.In diabetic rat, TGF-beta1 expression was upregulated by 1.65 times and Ec-NOS expression was 40% downregulated compared to control and insulin-treated diabetic rats in Western blot analysis. In control and insulin-treated diabetic rats, TGF-beta1 immunoreactivity was detected in fibroblasts and the collagen fibers, Ec-NOS immunoreactivity in the endothelial cells of blood vessels, and estrogen receptor alphaimmunoreactivity in the basal and intermediate cell layers of stratified squamous epithelium, smooth muscle fibers, and nerve fibers. In diabetic rat, expression of TGF-beta1, Ec-NOS, and estrogen receptor alphawas exhibited comparable cellular patterns of labeling, but signal intensity was increased in TGF-beta1 and decreased in Ec-NOS and estrogen receptor alpha. These results suggest that vaginal tissue fibrosis in diabetes mellitus may be caused by altered expression of TGF-beta1, NOS and estrogen. It also mplies that sexual arousal disorder and lack of vaginal lubrication in the diabetic women could be protected or delayed by controlling blood glucose levels.

Regulations of Bicarbonate Ions in Hypokalemic Rat Kidney / 대한해부학회지

A number of acid-base or electrolyte disorders are associated with decreased or increased HCO3- reabsorption in the renal tubules. There has been a general agreement that potassium depletion induces and maintains metabolic alkalosis in rats. However, many researchers have approached such issue only from functional studies to investigate Na+/H+ exchanger (NHE-3) and Na+/HCO(3-) cotransporter (NBC) activity which closely relates to potassium depletion. In addition the results obtained vary according to their researchers. Thus the present study was employed Western blot analysis and immunohistochemistry together, to examine the alterations of expression and distribution of NHE-3 and NBC-1 with reference to HCO3- reabsorption in the kidneys of rats fed potassium free diets according to the periods. Western blot analysis demonstrated that NHE-3 protein, ~83 kDa at molecular mass, was abundantly expressed in normal group. All potassium-depleted groups showed significantly increased NHE-3 protein compared to normal group. NBC-1 protein, ~110 kDa at molecular mass, was moderately expressed in normal group. All potassium-depleted groups had much higher amounts of the protein than normal group. There was a highly increased amount of NBC-1 protein especially in K-depleted 1 week group. Immunohistochemistry showed positive immunoreactivity of NHE-3 in the apical membranes and brush borders of proximal renal tubule cells. Its reactivity was most prominent in the S3.S1 and S2 had moderate immunoreactivity. Potassium-depleted groups had an identical pattern of cellular labeling of NHE-3 protein compared with that of normal group. However the signal intensity of NHE-3 protein in potassium-depleted groups was much higher than that of normal group. Immunoreactivity of NBC-1 was observed exclusively in the basolateral plasma membranes of proximal tubule cells. There was a strong reactivity in the S1 and S2, whereas S3 did not show any reactivity. Potassium-deprived rats exhibited an identical pattern of cellular labeling of NBC-1 protein compared with that of normal rats. However, the signal intensity of NBC-1 protein was markedly increased in potassium-deprived rats. These results suggest that increased NHE-3 and NBC-1 expression resulted from potassium depletion in the renal proximal tubules, enhances HCO3-reabsorption and consequently maintains metabolic alkalosis.

Localization of Cyclooxygenase Isozymes in Skin Wound Healing in Mouse / 대한해부학회지

Cyclooxygenase (COX)-1 and -2 expressions in the incisional wound healing of mouse skin were determined by immunohistochemistry and Western blot analysis. By Western blotting, compared to normal skin, COX-2 activity was increased at days 1, 4, 8, and 12 and was maximal at 4 day after incisional wound of mouse skin whereas COX-1 was barely detectable. In normal skin, COX-1 immunostaining was observed among the basal cells of epidermis whereas COX-2 immunostaining was detected in the more differentiated, suprabasal keratinocytes. At 1~4 days after wound, COX-2 staining was particularly prominent in the inflammatory cells, and at day 8, many macrophage-like cells were stained positively. COX-2 immunoreactive fibroblast, macrophage-like cells, and newly formed vascular endothelial cells were increased in number at 12 days after incision. These data suggest that COX-2 is constitutively expressed, just as is COX-1, in epidermis and is associated with keratinocyte differentiation. In addition, these findings support the well-established role for COX-2, the prostaglandins that they generate, as mediators of inflammatory response.

The cytotoxic effect of Vibrio vulnificus hemolysin on the mouse peritoneal macrophages

V. vulnificus is an estuarine bacterium which causes septicemia and shock in susceptible patients. The organism produces a hemolytic cytolysin (VvH), which has a membrane damaging effect on erythrocytes. To clarify the mechanisms by which VvH might contribute to virulence, we examined its effect on macrophages. When mouse peritoneal macrophages were harvested and co-cultured with hemolysin-positive V. vulnificus strains (100 bacteria/ cell), about 60% of the macrophages were killed; macrophages were not killed when co-cultured V. vulnificus strain CVD 707, a VvH-negative deletion mutant. Exposure of macrophages to filtered culture supernatants (2.5 HU/ml) and purified VvH (3 HU/ml) resulted in an increase in dead cells (80 and 90%, respectively), as determined by the trypan blue dye exclusion method and LDH release from macrophages was also increased (70 and 65.5%, respectively). The cytotoxic effect of VvH on macrophages was both the dose- and time-dependent. The VvH caused damage to the macrophage membrane and was blocked significantly by preincubation with cholesterol (p<0.01). Fetal bovine serum showed remarkable inhibition of VvH synthesis by V. vulnificus and inhibited VvH activity in culture supernatant. Cell viability was increased by 35% (p<0.01) and LDH release decreased by 28% (P<0.01) when macrophages were incubated with V. vulnificus (100 bacteria/ cell) in DMEM-10% FBS for 2 hr. Bacterial clearance activity of mice against V. vulnificus CVD 707 was decreased by pretreatment with 10 HU of VvH. This result suggests that the VvH can impair the membrane of macrophages and may play a role in the pathogenesis of V. vulnificus septicemia.